A projection of petroleum product trends identifies a large increase in distillate demands, particularly diesel fuel. Refiners are well aware of the processing variables available to them for increasing distillate production in a catalytic cracking operation. U.S. Pat. Nos. 3,894,931 and 3,894,933 address themselves to such operations. By a proper selection of FCC processing variables at low conversion and innovations involving catalyst type and high recycle of heavy cycle oil, distillate yield can be increased some considerable amount at the expense of gasoline yield. An increase by about 40% volume based on fresh feed in not unexpected. The yield of such distillate material may be substantially maximized by combining a hydrodewaxing operation in a manner to control cloud and pour points of distillate fuels obtained by the combination.
The processing arrangement of the present invention demonstrates how diesel fuels of high quality can be produced by blending a light fuel oil product of cracking, whether obtained by fluid catalytic cracking or hydrocracking, with a higher boiling dewaxed atmospheric gas oil and lighter virgin gas oil.